The field of the invention is telescoping columns.
Video, television, and motion picture cameras must often be positioned in a particular way for a video or film sequence. The camera must also often move or sweep in azimuth or elevation, and the entire camera may need to be translated or moved over the ground surface, e.g., to follow an action sequence or obtain a desired cinematographic effect. The camera may also have to be elevated or lowered at certain times.
Generally, all movement of the camera must be uniform and smooth without any bumping, rocking, tilting, vibration or other movement that will cause the recorded images to jump when viewed on a screen. For film sequences where the camera remains stationary, a simple support, e.g., a tripod may be sufficient. When the camera must be moved while operating, more sophisticated camera supports are required.
Ideally, the camera support should be lightweight and easily portable; capable of handling a wide range of loads; and support or move the camera with an absolute minimum of noise, vibration, rocking, tilting, jarring, etc. Depending on its specific application, the camera support may also need to be compact so that it may be used in cramped spaces.
Mobile and stationary camera pedestals are commonly used in television productions. These pedestals allow the camera to be raised and lowered and turned or swept (in azimuth). A tilt or elevation feature may also be included. These mobile units generally have three sets of paired wheels forming a three point support.
Within the pedestal, a mechanism for smoothly and quietly raising and lowering the camera platform is required. A purely manual system is generally insufficient since the weight of the camera may be substantial and the combination of inertia, friction and the application of the lifting or dropping force by hand will not ordinarily provide the necessary smooth, quiet and accurate positioning. Consequently, counterbalancing or compensation systems have been provided in camera pedestals to compensate for the weight of the camera and facilitate cinematographically acceptable changes in camera height or elevation. For example, Galione, U.S. Pat. No. 4,094,484 describes a pedestal having a self pumping action which provides a counterbalancing force by using compressed gas. Nakazawa et al, U.S. Pat. No. 4,757,970, discloses a television camera pedestal using constant torque springs to compensate for the camera weight. While these and other camera pedestals may have met with varying degrees of technical or commercial success, various disadvantages remain. For example, no known camera pedestal has a compressed gas compensation system which provides a uniform counterbalancing force throughout the full extension of the pedestal column. In addition, mechanical or spring actuated counterbalancing or compensation systems in pedestals are relatively complex and may be noisy in operation and difficult to set for a particular camera weight. These known pedestals also typically generate perceptible noise, especially during quick movements. In addition, they ordinarily have a limited range of movement or may tend to drift or sink from a desired position.
It is advantageous in filming or shooting to be able to position the camera to a very low position. This requires relatively short column sections in telescoping type pedestals. On the other hand, to also have a sufficient maximum height, a relatively large number of column sections is required, heretofore making for a bulky pedestal.
Accordingly, it is an object of the invention to provide an improved camera pedestal which has uniform camera weight compensation throughout the full extension of the pedestal.
It is a further object of the invention to provide such a camera pedestal which is configured for ease of use and is compact yet offers exceptionally low camera positions while still having a large elevation range.
It is yet another object of the invention to provide such a camera pedestal which can be mounted in, and which has an exceptionally quiet steering assembly which can engage and operate a steering system of, a camera dolly. Other and further objects and advantages will appear hereinafter.